8000 rpm/300 bhp 3.2 rebuild

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911hillclimber
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by 911hillclimber »

Bitter-sweet day on the Lola.
Good bits:
The engine RUNS!
Using the old distributor and system on the top 6 plugs and after freeing off 2 of the 4 carb floats it coughed and spat and farted and burst into life.

Sounds absolutely glorious, the throttle response is out of this world.

I even started it twice to be sure, same result. Both sides of the engine same heat too, so all 6 behaving.

Bad bit:

Mike's lovely 12 plug distributor does not fit in the engine well, the drive gear mesh is too sloppy.
The back lash must be 5 degrees, so the timing would be wondering around all over the place.

Shame, have to hope Clewett and Electromotive come true. :?

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73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
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jb
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by jb »

Great news Graham.
It sounds like it will be fabulous when all set up.
It is a shame about the XDI but my fingers are crossed for you getting a quick result from Clewett.
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Gary71
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by Gary71 »

Excellent news Graham :)
Nine One One
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by Nine One One »

How long have you run it for - you mention excellent throttle response and both sides get to equal temperature.

Remember you have to run the cam in, which I thought was happening on the rolling road?
911hillclimber
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by 911hillclimber »

Today I wanted to prove the engine wouldstart and runsimplytosee theoil pressure and listen for any untoward noises, but no more.
I ran it for no more than2 to 3 mins.

I've cancelled the rolling road, due next week as I don't have the right ignition system due to failure of the Clewett controller, now on its way back to Virginia, USA
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by wadsworthi »

Well done Graham, really pleased that you have got it running. You should be really satisfied that all of your engineering work has been successful! The ignition will come together soon.

I think you have mentioned that your original distributor was off a 2.7 engine and I guess Mike’s is probably a 3 litre with different cogs and possibly runs in a different direction.
911hillclimber
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by 911hillclimber »

Yes, my 'current ' dist is off a 2.7 clockwise. Allegedly a 2.7, but who knows, it works!

Mike's came of a 2.8 twin plug engine way way back. Has Hall sensor not breakers, and is clock wise too.
Pity, as the unit is a super neat way to do the twin plug ignition, though I think it is worth a lot!
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
911hillclimber
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by 911hillclimber »

Electromotive claim the XDi unit i returned is perfect.

They suggest the alternative Hall Effect sensor is used to help make the unit function.
This I can buy for $150 plus post plus Customs duty.

They hope I'm having a nice day and what do I want to do now.

:evil:
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
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Jonny Hart
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by Jonny Hart »

^ to use an American expression, that’s BS!

The XDI manual shows the ECU has 3 sensor connections of signal, ground and shield. That’s for a variable reluctor which is what you have. A Hall sensor needs a 12V feed so it would be signal, 12V and ground so it could not possibly work with the supplied sensor loom. There is also no mention of Hall effect sensor in the XDI manual at all.

Also, this is meant to be a complete kit so should have come with the right sensor in the first place!
911hillclimber
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by 911hillclimber »

I was so hoping you would respond Jonny.

It is true what you say, but on the electromotive web there is a page or two of fault finding and reasoning for failures.
It is under 'Other Electrical Noise'
It states that other sources of noise exist beyond a 'dirty' aftermarket starter.
1
Ensure the power for the XDi is isolated from the starter by the battery, allowing it to act as a filter for the noise.
I don't understand how to do that.
2
Make sure the cable/wires to the starter are not close to the sensor on the engine.
My starter routing is 8" away. Would that be "close"? They do not define the min distance.
3
Other noises from electric water pumps, fans,:
"The use of a Hall Effect sensor can resolve most of these problems".

They sell the Hall Sensor for $149 plus shipping/duty, so about £200 delivered to my garage.
They now have my 'trouble-free' XDi unit.

Stephanie at Electromotive has asked how I would like to proceed, and to have a nice day.

I'm stuffed.
Pay for the sensor, pay for the returns.

I have politely asked they send the XDi and the sensor free to me.

Very tempted to tell them to stuff it and pay a lot more for a real ECU from DTA.
Mrs HC says buy and take the cheaper option.

I can change the power lines to the starter to increase the distance from the sensor if I try hard enough.

Utterly exasperated over the whole lot.

This is from the Clewett site, not the Hall Sensor is not compatible with the XDI!

Hall crank sensor for slow cranking speeds and starter motor related electrical noise issues.

This hall sensor is compatible with Electromotive's TEC-s, TEC-s200, TEC-gt, TEC-gt200 and TEC-3r engine management systems and the XDi-2 and XDi200 Ignition systems.

The hall sensor fits the same brackets as the 1/2" magnetic sensor. Simply install the new hall sensor as you would a magnetic sensor and attach the 3 pin connector to the existing wire harness. Attach the included yellow wire to switched ignition. In the engine program file, go to advanced settings and change the crank sensor to 'Hall'. Save the file and program the ECU.


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73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
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Jonny Hart
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by Jonny Hart »

^. Yes, so the extra wires in the harness pictured provide the power. You have been provided a VR type sensor in your kit so surely the onus is on the kit seller to provide the right equipment?

It’s true that the Hall sensor has the signal processing in the sensor so is less prone to noise. A VR type pickup may also not provide enough amplitude signal at low RPM but it would have to be far lower than cranking speed or the sensor gap be to large. You have been through this though so I don’t think that is the case.

Question for the guys who tested the sensor: what was the pk-to-pk voltage of the sensor output at crank speed?

Usually, noise results in misfires etc, not a complete ‘dead’ situation. You should still get some kind of flash on the LED. As noise is effectively voltage spikes, you would get MORE flashing with noise, not less.

Besides, you tested the input on your lathe so no starter noise at all…

Ask them for a video of your unit working with the same type of VR sensor.
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by Mike911scrs »

Hi 911hillclimber

I have looked at the photo of you unit bolted to the chassis and it has on it XDI, as the Hall Sensor is from your list only fits the XDI-2 unit,

"This hall sensor is compatible with Electromotive's TEC-s, TEC-s200, TEC-gt, TEC-gt200 and TEC-3r engine

management systems and the XDi-2 and XDi200 Ignition systems."

can you plug your laptop into the XDI unit to re-set the crank sensor to the Hall sensor???,

" In the engine program file, go to advanced settings and change the crank sensor to 'Hall'. Save the file and program the ECU"

regards mike
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Jonny Hart
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by Jonny Hart »

So recap:

911hillclimber was sent an XDI and a VR sensor.

The XDI manual says VR (magnetic) sensor, no mention of Hall.

The vendor is suggesting a Hall sensor but the XDI does not appear to support that.

Wow.
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by RobFrost »

I'd be aiming to speak with electromotive's most senior engineer to get reference voltages and signal to noise ratio that the unit finds acceptable, and at what rpm? If what they say is correct they must be able to confirm that the voltage being generated on your car is too low or the noise too great.

What is their test rig on which it was found to be working, what speed does it crank at, what sensor signal is used and what signal to noise ratio?

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911hillclimber
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Re: 8000 rpm/300 bhp 3.2 rebuild

Post by 911hillclimber »

Thank you Jonny!
Rob and Chris found a 4 volt pk to pk in the end from the sensor at engine cranking speed.
The signal was very precise, but the face of the VR was 10 thou off the crank wheel.
Clewett said the engine would not work with this air gap, a 40 thou gap was needed.

Mind you, he said I had destroyed the XDi input circuit due to electrical noise too.

Both companies have no positive answer.
I have asked if the Hall sensor is compatible to the XDi. Their web sites say no, but they recommend the sensor!

Weekend in the way, and their techie guy works one day a week.

Mike, there is no facility to get into the XDi, it is the XDi2 and 'upwards' that has any way to talk to the unit.

I am expecting the response to be from the USA 'You need to buy a better unit from us'.

Just paused to have breakfast before going to our hillclimb track to do some ground work this morning.
Rob, and everyone, i will collate your responses ans questions and put them to the USA companies.

They have ignored all such questions in the past, but will ask.

I'm now cancelling event entries, all down to this poor product miss sold to me I feel.

The more I see of these companies and this product the more i feel like telling them to stuff it up their arses and simply move to DTA retaining the coil packs and the crank trigger.
The T8 DTA is hopelessly over specified for me, but does twin plug, easy to talk to and I can visit in 1 hour.

By the time I pay everything it will be close to 50% of the cost to get it back with some sensor or other if one for the XDi exists.
Going to see what i may be able to do to get a refund via VISA as I think I have enough background info to put a good case forward as this product is not suitable for intended use,
or Not Fit for Purpose, in English.

got to leave now to errect some signs. doubt i will be racing before May.
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
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